X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12
X + 15 = 3 x X - 9
15 + 9 = 3 x X - X
24 = 2 x X
X = 24 : 2
X = 12
Vậy X = 12